We propose to study under controlled conditions the effect of an administrative and educational intervention in an academic medical outpatient service upon patient outcomes, provider behaviors, and costs. The basic experimental design will be that of a randomized controlled trial of an intervention utilizing pretest (Time 1) and posttest (Time 2) measurements to determine the direction and significance of changes in dependent variables. The intervention will consist of a reorganization of two out of four equivalent outpatient services, each comprised of 15 house officers and staff physicians providing care for approximately 2,000 patients, into six small group practices with continued responsibility to provide primary care to a defined patient panel. An educational program will provide clinicians with appropriate management skills and patient care information in order to: (1) facilitate appropriate patient care; and (2) use resources rationally. The primary objective of this study is to evaluate the effectiveness of this model in terms of the goals of primary care: continuity, comprehensiveness, coordination, and accessibility. In addition, we will evaluate the quality of care and cost effectiveness of the proposed model. The evaluation will be comprehensive and will include measures of provider productivity, attitude, and satisfaction, quality of care, patient satisfaction, and costs. Data will be obtained from validated test instruments and pre-existing data sources. Quality of care will be measured by both implicit and explicit criteria. This information will serve as a guide to the value and feasibility of implementing the group practice structure on a more widespread basis in academic medical settings.